8 models
Ranked by FrontierMath
Reasoning Tools JSON 97.6

GPT-6 Astra is OpenAI's flagship model for demanding end-to-end work. It is suited for advanced analysis, software engineering, deep research, scientific work, and document creation, with particular strengths in long-horizon...

openai/gpt-6-astra 2026-09-04 1.05M context $10/M input $50/M output
18 providers
Reasoning Tools JSON 89.0

GPT-5.6 Sol is the flagship model in OpenAI's GPT-5.6 series. It is suited for complex reasoning, coding, and agentic workflows, and is particularly strong at command-line and multi-step coding tasks...

openai/gpt-5.6-sol 2026-07-09 1.05M context $2/M input $10/M output
36 providers
Reasoning Tools JSON 84.9

GPT-5.6 Terra is a balanced model in OpenAI's GPT-5.6 series, positioned between the flagship Sol tier and the cost-efficient Luna tier. It is suited for everyday coding, reasoning, and agentic...

openai/gpt-5.6-terra 2026-07-09 1.05M context $2/M input $12/M output
35 providers
Reasoning Tools JSON 78.6

GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for...

openai/gpt-5.6-luna 2026-07-09 1.05M context $0.2/M input $1.2/M output
36 providers
Reasoning Tools JSON 39.6

GPT-5.5 Pro is OpenAI’s high-capability model optimized for deep reasoning and accuracy on complex, high-stakes workloads. It features a 1M+ token context window (922K input, 128K output) with support for...

openai/gpt-5.5-pro 2026-04-23 1.05M context $30/M input $180/M output
18 providers
Reasoning Tools 38.0

GPT-5.4 Pro is OpenAI's most advanced model, building on GPT-5.4's unified architecture with enhanced reasoning capabilities for complex, high-stakes tasks. It features a 1M+ token context window (922K input, 128K...

openai/gpt-5.4-pro 2026-03-05 1.05M context $30/M input $180/M output
19 providers
Reasoning Tools JSON 35.4

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token...

openai/gpt-5.5 2026-04-23 1.05M context $5/M input $30/M output
46 providers
Reasoning Tools JSON 27.1

GPT-5.4 is OpenAI’s latest frontier model, unifying the Codex and GPT lines into a single system. It features a 1M+ token context window (922K input, 128K output) with support for...

openai/gpt-5.4 2026-03-05 1.05M context $2.5/M input $15/M output
42 providers